Figure 1

Various threats multipotential stromal cells face at the delivery site leading to loss of cells. Leukocytes and macrophages that are brought into the multipotential stromal cell (MSC) implantation site as part of the nonspecific inflammatory response can secrete proinflammatory cytokines and chemokines, as well as increase cellular stress and generate reactive oxygen species (ROS) that might activate apoptotic cascades. Wound and ischemic sites where MSC therapy is usually required are low in vascularity and are hypoxic regions, which might add to MSC cell stress. Also, lack of attachment of MSC to the extracellular matrix (ECM) may cause MSC to detach, undergo anoikis and ultimately lead to cell death.